1. Field of Invention
This invention relates to molded containers and closures, and in particular to a container having a plurality of teeth on its exterior surface for engaging mating teeth on a closure, and a method and apparatus for forming such a container.
2. Description of the Prior Art
Containers made of plastic, glass and other like materials are usually molded in dies comprising at least two sections which are adapted to be separated at a parting line to permit removal of the molded article from the die cavity. The articles which are molded in such dies, must be so designed as to permit the die section to be parted free of the articles without any interference with the surfaces of the articles. Preferably, the surfaces of such articles have a so-called positive "draft" with respect to the direction in which the die sections are moved during parting to insure that there is no interference between the molded article and the interior surfaces of the die sections during parting.
Some molded containers are used for substances such as drugs, chemicals and the like which are potentially poisonous, and the containers therefor are preferably provided with closures which resist opening by small children. A number of such containers and closures have been developed which employ one or more teeth on the container which are adapted to be engaged by mating teeth on a closure to prevent removal of the closure except by flexing or deformation of the closure or container. Packages of this type are disclosed in a number of patents including the following U.S. Pat. Nos. 2,827,193 to Martin, 3,101,856 to Whiteman, Jr., 3,233,769 to Jessop, 3,360,147 to Schaefer, 3,422,978 to Quackenbush, 3,445,022 to Cilluffo, 3,698,584 to Miller, 3,830,381 to Uhlig and 3,857,508 to LaBarge et al. Another disclosure of interest with respect to teeth on a molded container is contained in British Patent Specification No. 847,332.
The prior art does not disclose a container having a plurality of integral locking teeth thereon which can be easily molded without interference between the teeth and the mold when the mold sections are parted.